[nautilus] batch-rename-dialog: use GTask appropiately

[Carlos Soriano Sánchez <csoriano src gnome org>]

commit 819546836462408022b1ebf8f5d8569542dfa831
Author: Carlos Soriano <csoriano gnome org>
Date:   Tue Sep 6 17:27:12 2016 +0200

    batch-rename-dialog: use GTask appropiately
    
    The Gtask has to finish only when all the internal async call are ready,
    doing the other way around is conceptually wrong and will cause problems
    if we rely on the task for checking the status of the general operation.
    
    For that implement a correct GTask handling, waitig with a mutex and
    condition for all async calls to be ready, and only then mark the task
    as finished.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=770586

 src/nautilus-batch-rename-dialog.c |  246 +++++++++++++++++++++++++-----------
 1 files changed, 173 insertions(+), 73 deletions(-)
---
diff --git a/src/nautilus-batch-rename-dialog.c b/src/nautilus-batch-rename-dialog.c
index c431353..9f7c3b2 100644
--- a/src/nautilus-batch-rename-dialog.c
+++ b/src/nautilus-batch-rename-dialog.c
@@ -82,17 +82,12 @@ struct _NautilusBatchRenameDialog
     GHashTable *create_date;
     GList *selection_metadata;
 
-    /* check if all files in selection have the same parent */
-    gboolean same_parent;
     /* the index of the currently selected conflict */
     gint selected_conflict;
     /* total conflicts number */
     gint conflicts_number;
 
-    gint checked_parents;
     GList *duplicates;
-    GList *distinct_parents;
-    GTask *conflicts_task;
     GCancellable *conflict_cancellable;
     gboolean checking_conflicts;
 
@@ -1400,7 +1395,6 @@ update_listbox (NautilusBatchRenameDialog *dialog)
     }
 }
 
-
 void
 check_conflict_for_files (NautilusBatchRenameDialog *dialog,
                           NautilusDirectory         *directory,
@@ -1510,6 +1504,7 @@ check_conflict_for_files (NautilusBatchRenameDialog *dialog,
                 have_conflict = TRUE;
             }
         }
+
         if (!have_conflict)
         {
             tag_present = g_hash_table_lookup (names_conflicts_table, new_name->str) != NULL;
@@ -1531,59 +1526,154 @@ check_conflict_for_files (NautilusBatchRenameDialog *dialog,
         g_free (parent_uri);
     }
 
-    /* check if this is the last call of the callback. Update
-     * the listbox with the conflicts if it is. */
-    if (dialog->checked_parents == g_list_length (dialog->distinct_parents) - 1)
-    {
-        dialog->duplicates = g_list_reverse (dialog->duplicates);
-
-        dialog->checking_conflicts = FALSE;
-
-        update_listbox (dialog);
-    }
-
-    dialog->checked_parents++;
-
     g_free (current_directory);
     g_hash_table_destroy (directory_files_table);
     g_hash_table_destroy (new_names_table);
     g_hash_table_destroy (names_conflicts_table);
 }
 
+static gboolean
+file_names_list_has_duplicates_finish (NautilusBatchRenameDialog  *self,
+                                       GAsyncResult               *res,
+                                       GError                    **error)
+{
+  g_return_val_if_fail (g_task_is_valid (res, self), FALSE);
+
+  return g_task_propagate_boolean (G_TASK (res), error);
+}
+
 static void
-file_names_list_has_duplicates_callback (GObject      *object,
-                                         GAsyncResult *res,
-                                         gpointer      user_data)
+on_file_names_list_has_duplicates (GObject      *object,
+                                   GAsyncResult *res,
+                                   gpointer      user_data)
 {
-    NautilusBatchRenameDialog *dialog;
+    NautilusBatchRenameDialog *self;
+    GError *error = NULL;
+    gboolean success;
 
-    dialog = NAUTILUS_BATCH_RENAME_DIALOG (object);
+    self = NAUTILUS_BATCH_RENAME_DIALOG (object);
+    success = file_names_list_has_duplicates_finish (self, res, &error);
+
+    if (!success)
+    {
+        return;
+    }
+
+    update_listbox (self);
+}
 
-    if (g_cancellable_is_cancelled (dialog->conflict_cancellable))
+static void
+on_file_names_list_has_duplicates_distinct_parents (GObject      *object,
+                                                    GAsyncResult *res,
+                                                    gpointer      user_data)
+{
+    NautilusBatchRenameDialog *self;
+    GError *error = NULL;
+    gboolean success;
+
+    self = NAUTILUS_BATCH_RENAME_DIALOG (object);
+    success = file_names_list_has_duplicates_finish (self, res, &error);
+
+    if (!success)
     {
         return;
     }
 
-    if (dialog->same_parent)
+    self->duplicates = g_list_reverse (self->duplicates);
+    self->checking_conflicts = FALSE;
+    update_listbox (self);
+}
+
+typedef struct
+{
+    GList *directories;
+    GMutex wait_ready_mutex;
+    GCond wait_ready_condition;
+    gboolean directory_conflicts_ready;
+} CheckConflictsData;
+
+static void
+on_directory_conflicts_ready (NautilusDirectory *conflict_directory,
+                              GList             *files,
+                              gpointer           callback_data)
+{
+    NautilusBatchRenameDialog *self;
+    GTask *task;
+    CheckConflictsData *task_data;
+    GCancellable *cancellable;
+
+    task = G_TASK (callback_data);
+    task_data = g_task_get_task_data (task);
+    cancellable = g_task_get_cancellable (task);
+    self = NAUTILUS_BATCH_RENAME_DIALOG (g_task_get_source_object (task));
+    if (!g_cancellable_is_cancelled (cancellable))
     {
-        update_listbox (dialog);
+        check_conflict_for_files (self, conflict_directory, files);
     }
+
+    g_mutex_lock (&task_data->wait_ready_mutex);
+    task_data->directory_conflicts_ready = TRUE;
+    g_cond_signal (&task_data->wait_ready_condition);
+    g_mutex_unlock (&task_data->wait_ready_mutex);
 }
 
 static void
-on_call_when_ready (NautilusDirectory *directory,
-                    GList             *files,
-                    gpointer           callback_data)
+file_names_list_has_duplicates_distinct_parents (GTask *task)
 {
-    check_conflict_for_files (NAUTILUS_BATCH_RENAME_DIALOG (callback_data),
-                              directory,
-                              files);
+    NautilusBatchRenameDialog *self;
+    CheckConflictsData *task_data;
+    NautilusDirectory *conflict_directory;
+    GList *directories;
+    GList *l;
+    const gchar *directory_conflict_uri = NULL;
+
+    self = g_task_get_source_object (task);
+    task_data = g_task_get_task_data (task);
+
+    g_mutex_init (&task_data->wait_ready_mutex);
+    g_cond_init (&task_data->wait_ready_condition);
+
+    directories = batch_rename_files_get_distinct_parents (self->selection);
+    /* check if this is the last call of the callback */
+    for (l = directories; l != NULL; l = l->next)
+    {
+        if (g_task_return_error_if_cancelled (task))
+        {
+            return;
+        }
+
+        g_mutex_lock (&task_data->wait_ready_mutex);
+        task_data->directory_conflicts_ready = FALSE;
+
+        directory_conflict_uri = l->data;
+        conflict_directory = nautilus_directory_get_by_uri (directory_conflict_uri);
+
+        nautilus_directory_call_when_ready (conflict_directory,
+                                            NAUTILUS_FILE_ATTRIBUTE_INFO,
+                                            TRUE,
+                                            on_directory_conflicts_ready,
+                                            task);
+
+        /* We need to block this thread until the call_when_ready call is done,
+         * if not the GTask would finalize. */
+        while (!task_data->directory_conflicts_ready)
+        {
+            g_cond_wait (&task_data->wait_ready_condition,
+                         &task_data->wait_ready_mutex);
+        }
+
+        g_mutex_unlock (&task_data->wait_ready_mutex);
+
+        nautilus_directory_unref (conflict_directory);
+    }
+
+  g_task_return_boolean (task, TRUE);
 }
 
 static void
 file_names_list_has_duplicates_async_thread (GTask        *task,
                                              gpointer      object,
-                                             gpointer      task_data,
+                                             gpointer      data,
                                              GCancellable *cancellable)
 {
     NautilusBatchRenameDialog *dialog;
@@ -1594,15 +1684,16 @@ file_names_list_has_duplicates_async_thread (GTask        *task,
     NautilusFile *file;
     GString *file_name;
     GString *new_name;
-    NautilusDirectory *parent;
     gboolean have_conflict;
     gboolean hash_table_insertion;
+    gboolean same_parent;
     gchar *name;
     GHashTable *directory_names_table;
     GHashTable *new_names_table;
     GHashTable *names_conflicts_table;
     gint exists;
     ConflictData *conflict_data;
+    g_autoptr (GSource) chained_call_source = NULL;
 
     dialog = NAUTILUS_BATCH_RENAME_DIALOG (object);
 
@@ -1617,25 +1708,11 @@ file_names_list_has_duplicates_async_thread (GTask        *task,
 
     /* If the batch rename is launched in a search, then for each file we have to check for
      * conflicts with each file in the file's parent directory */
-    if (dialog->distinct_parents != NULL)
+    same_parent = !NAUTILUS_IS_SEARCH_DIRECTORY (dialog->directory);
+    if (!same_parent)
     {
-        for (l1 = dialog->distinct_parents; l1 != NULL; l1 = l1->next)
-        {
-            if (g_cancellable_is_cancelled (cancellable))
-            {
-                return;
-            }
-
-            parent = nautilus_directory_get_by_uri (l1->data);
+        file_names_list_has_duplicates_distinct_parents (task);
 
-            nautilus_directory_call_when_ready (parent,
-                                                NAUTILUS_FILE_ATTRIBUTE_INFO,
-                                                TRUE,
-                                                on_call_when_ready,
-                                                dialog);
-        }
-
-        g_task_return_pointer (task, object, NULL);
         return;
     }
 
@@ -1744,7 +1821,28 @@ file_names_list_has_duplicates_async_thread (GTask        *task,
 
     dialog->checking_conflicts = FALSE;
 
-    g_task_return_pointer (task, object, NULL);
+    g_task_return_boolean (task, TRUE);
+}
+
+static void
+destroy_conflicts_task_data (gpointer data)
+{
+    CheckConflictsData *task_data = data;
+
+    if (task_data->directories)
+    {
+        g_list_free (task_data->directories);
+    }
+
+    if (&task_data->wait_ready_mutex)
+    {
+        g_mutex_clear (&task_data->wait_ready_mutex);
+    }
+
+    if (&task_data->wait_ready_condition)
+    {
+        g_cond_clear (&task_data->wait_ready_condition);
+    }
 }
 
 static void
@@ -1752,19 +1850,23 @@ file_names_list_has_duplicates_async (NautilusBatchRenameDialog *dialog,
                                       GAsyncReadyCallback        callback,
                                       gpointer                   user_data)
 {
+    g_autoptr (GTask) task = NULL;
+    CheckConflictsData *task_data;
+
     if (dialog->checking_conflicts == TRUE)
     {
         g_cancellable_cancel (dialog->conflict_cancellable);
+        g_clear_object (&dialog->conflict_cancellable);
     }
 
     dialog->conflict_cancellable = g_cancellable_new ();
 
     dialog->checking_conflicts = TRUE;
-    dialog->conflicts_task = g_task_new (dialog, dialog->conflict_cancellable, callback, user_data);
-
-    g_task_run_in_thread (dialog->conflicts_task, file_names_list_has_duplicates_async_thread);
 
-    g_object_unref (dialog->conflicts_task);
+    task = g_task_new (dialog, dialog->conflict_cancellable, callback, user_data);
+    task_data = g_new0(CheckConflictsData, 1);
+    g_task_set_task_data (task, task_data, destroy_conflicts_task_data);
+    g_task_run_in_thread (task, file_names_list_has_duplicates_async_thread);
 }
 
 static void
@@ -2060,6 +2162,7 @@ update_display_text (NautilusBatchRenameDialog *dialog)
     TagData *tag_data;
     TagData *tag_data0;
     TagData *tag_data00;
+    gboolean same_parent;
 
     tag_data = g_hash_table_lookup (dialog->tag_info_table, NUMBERING);
     tag_data0 = g_hash_table_lookup (dialog->tag_info_table, NUMBERING0);
@@ -2100,16 +2203,25 @@ update_display_text (NautilusBatchRenameDialog *dialog)
     }
 
     dialog->new_names = batch_rename_dialog_get_new_names (dialog);
-    dialog->checked_parents = 0;
 
     if (have_unallowed_character (dialog))
     {
         return;
     }
 
-    file_names_list_has_duplicates_async (dialog,
-                                          file_names_list_has_duplicates_callback,
-                                          NULL);
+    same_parent = !NAUTILUS_IS_SEARCH_DIRECTORY (dialog->directory);
+    if (same_parent)
+    {
+        file_names_list_has_duplicates_async (dialog,
+                                              on_file_names_list_has_duplicates,
+                                              NULL);
+    }
+    else
+    {
+        file_names_list_has_duplicates_async (dialog,
+                                              on_file_names_list_has_duplicates_distinct_parents,
+                                              NULL);
+    }
 }
 
 static void
@@ -3172,7 +3284,6 @@ nautilus_batch_rename_dialog_finalize (GObject *object)
         g_hash_table_destroy (dialog->create_date);
     }
 
-    g_list_free_full (dialog->distinct_parents, g_free);
     g_list_free_full (dialog->new_names, string_free);
     g_list_free_full (dialog->duplicates, conflict_data_free);
 
@@ -3256,17 +3367,6 @@ nautilus_batch_rename_dialog_new (GList             *selection,
 
     nautilus_batch_rename_dialog_initialize_actions (dialog);
 
-    dialog->same_parent = !NAUTILUS_IS_SEARCH_DIRECTORY (directory);
-
-    if (!dialog->same_parent)
-    {
-        dialog->distinct_parents = batch_rename_files_get_distinct_parents (dialog->selection);
-    }
-    else
-    {
-        dialog->distinct_parents = NULL;
-    }
-
     update_display_text (dialog);
 
     fill_display_listbox (dialog);